The present invention relates to a material and a manufacturing method of a tank of an oil-immersion type power distribution transformer for indoor and outdoor use.
1. PRIOR ART
FIG. 2 is a schematic drawing showing a configuration of an oil-immersion type transformer a body of which is contained in a metallic tank so as to be disposed on an outdoor pole and in an electric room and so on. An inner structure consisting of an iron core 4 and a coil 3 is contained in the tank 1 to which a bushing 6 is attached. Insulation oil 5 is filled in the tank, and a top of the tank is closed by a lid 2. The tank 1 is an assembled structure of steel plates welded with one another so as to prevent the insulation oil from leaking through weld seams. Further, in order to enhance the rust-proof characteristic of the tank and to improve the finish appearance of the same, the whole surface of the tank is coated with a paint having excellent weather resistance.